A Quick Guide to Personality Disorders
People with personality disorders have difficulties building and maintaining interpersonal relationships. They behave in ways that appear odd or disturbing to those whose mode of thinking and behaving fall within what's considered to be socially and culturally "normal." Yet people with personality disorders believe they are behaving appropriately, even when their actions prevent them from forming close relationships, being successful at work and navigating successfully through life in general.

According to the National Institute of Mental Health (NIMH), an estimated 9.1 percent of Americans aged 18 and older have a diagnosable personality disorder. Personality disorders form in adolescence or early adulthood. While some of them moderate during middle age without treatment, others persist into old age despite treatment.

The descriptions of personality disorders that follow summarize information from the Web sites for the NIMH, MedlinePlus, National Alliance on Mental Illness, Psychiatric Disorders.com and Mental Health America.

Antisocial personality disorder: Characterized by self-serving, impulsive, irresponsible, aggressive, intimidating, violent behaviors; a disregard for social rules or laws; callous indifference to and lack of empathy and respect for others' rights, feelings and well-being. No sense of guilt or remorse for the harm they inflict. High risk for criminal behavior and substance abuse, especially alcoholism, which helps relieve tension, irritability and boredom.

Avoidant personality disorder: Characterized by extreme shyness, social avoidance and sensitivity to disapproval, criticism and rejection; feeling inadequate; fearing saying or doing something others will think is foolish. Individuals with avoidant personality disorder frequently avoid social interaction for fear of being ridiculed, humiliated or disliked, yet they're distressed about their inability to form close relationships.

Borderline personality disorder: Characterized by unstable and intense moods, emotions, behaviors and interpersonal relationships; fluctuating self-image; self-destructive acts and self-mutilation; forming intense friendships; quick to dissolve relationships over a perceived slight; fear of abandonment; impulsivity, chronic boredom; angry outbursts; distorted view of the world as all good or all bad; unsure of own identity.

Dependent personality disorder: Characterized by dependent and submissive behaviors; relying on others to make their decisions; intense fear of separation, abandonment or rejection; requiring excessive reassurance and advice; easily hurt by criticism or disapproval; inability to function when alone; feeling devastated when close relationships end; lacking in self-confidence.

Histrionic personality disorder: Characterized by excessively emotional, dramatic or seductive behaviors in order to be the center of attention; being easily influenced by others; constantly seeking reassurance or approval and being highly sensitive to criticism or disapproval; highly concerned with their looks; overestimating the intimacy of their relationships; blaming others for failures and disappointments; low tolerance for frustration or delayed gratification; mercurial emotions; yet able to function successfully in social and work life.

Narcissistic personality disorder: Characterized by an exaggerated sense of self-importance; exaggeration of own achievements and talents; preoccupation with fantasies of own success, beauty, intelligence or ideal love; an obsession with the pursuit of self-interests; interpersonal exploitation; needing constant attention and admiration; oversensitivity to failure; extreme mood swings between self-admiration and insecurity; reacting to criticism with rage, shame or humiliation; expectations of favorable treatment; disregarding others' feelings; being incapable of empathy.

Obsessive-compulsive personality disorder: Characterized by high conscientiousness; high aspirations; perfectionism; assuming ever more responsibility because they're never satisfied with their achievements; being reliable, dependable, orderly and methodical; being inflexible in changing circumstances; being highly cautious; weighing all aspects of problems; paying attention to every detail (which delays decisions and completing tasks); feeling isolated or helpless when their emotions aren’t under control, events are unpredictable or they must rely on others.

Paranoid personality disorder: Characterized by interpreting others' actions as deliberately threatening or demeaning; being untrusting, unforgiving, and prone to unjustifiable angry or aggressive outbursts; perceiving others as unfaithful, disloyal, condescending, deceitful or having hidden motives; guardedness; jealously; secretiveness; scheming; emotional coldness; excessive seriousness; expecting that others will exploit them; inability to work with others; poor self-image; social isolation; detachment; hostility.

Schizoid personality disorder: Characterized by introversion, withdrawal, isolation, emotional coldness and distance; aloofness and detachment; absorbed with own thoughts and feelings; fearful of closeness and intimacy with others; avoidance of social activities that require significant contact with others; not wanting or enjoying close relationships, including with family.

Schizotypal personality disorder: Characterized by peculiar, odd or eccentric manners of speaking or dressing; strange, outlandish or paranoid beliefs; difficulties forming relationships; experiencing anxiety in social situations; inappropriate or no reaction during conversations; talking to themselves; believing they can tell the future or read others' minds.

To find help for someone with a personality disorder contact your local NAMI chapter or visit helpguide.org.